json转字符串

function json2str(o) {
	function isArray(o) {
	 	return Object.prototype.toString.call(o) === '[object Array]'; 
	}
	
	var arr = [];
	var fmt = function(s) {
		var type = typeof s;
		if (type == 'object' && s != null){
			return self.json2str(s);
		}
		if(type === "number"){
			return s;
		}
		return type==="string" ? '"' + s.replace(/\"/g,"\\\"") + '"' : s;
	}
	if(isArray(o)){
		for(var i = 0,length = o.length;i<length;i++){
			arr.push(fmt(o[i]));
		}
		return '[' + arr.join(',') + ']';
	}else{
		for (var i in o){
			arr.push('"' + i + '":' + fmt(o[i]));
		}
		return '{' + arr.join(',') + '}';
	}
}

为了跟jquery兼容，修改了一下